[MaddMartigan]

My car was running ok until this past Saturday. I have been running a tune that was created by reading the T4M0 EEC and then modifying it for my injectors, MAF, displacement and lack of EGR. I have also run the J4J1 modded bin file from the Tweecer Yahoo group as well as a slightly modified of that bin file as well. No matter what I run, the car is smoking from running too rich and won't really run at all. The wideband O2 is saying that it's running 7.4:1 AFR or so and it just doesn't want to run.

This all basically came out of the blue. I can't go back to a stock setting since I am running 42lb. injectors and a 90mm LMAF.

Any thoughts or ideas?

[rockin_rick]

Not that I'm doubting (totaly) that your running rich, but I don't think that the LC-1 reads down to 7.4. Perhaps your WB transfer is skewed, and you are really running closer to stoich.

Rick

[MaddMartigan]

Well, the car is smoking like a train and the plugs are all blackened. The smell of fuel is VERY heavy. I pulled the wideband to recalibrate it and it was pretty well blackened as well.

[MaddMartigan]

Ok, I have double-checked all of the plugs and they are all blackened because of too much fuel. I have changed to another EEC and I get the same results. I can read and write the Tweecer just fine and I can read the EEC just fine as well.

I have an Innovate LC-1 wideband O2 sensor and it is no longer providing a reading through Logworks (not too surprising) and I can get a reading that does change but I'm not sure if it is the correct reading. The Innovate reading just shows single digit numbers so I am guessing that it's not compatible. If I set it to the PLX setting in Calcon I see numbers that are a little more reasonable (if 11.3 AFR is reasonable) but I am not sure if that is correct either. Again, the car is smoking(all fuel) a lot and won't idle obviously.

I have checked everything mechanical that I can check. I am really at a loss here.

Edited to say that I am actually dripping fuel out of the driver's side of the engine. What are the chances that more than one injector could be hung and staying open? If that is true, is there any way to fix a stuck injector?

[MaddMartigan]

27 views and one reply.


Very helpful.

[fireguy50]

Have you check other parts of the car like fuel pressure?
any computer fault codes?

[MaddMartigan]

Have you check other parts of the car like fuel pressure?
any computer fault codes?

Well, there aren't any KOEO codes and I can't get it to run well enough to check for KOER codes.

The fuel pressure appears to be running right at 41-42psi. One thing that I thought was strange is that the fuel pressure bleeds off immediately when I turn off the key. I was told that it could be the check ball in the fuel pump that would cause this if it doesn't work properly but that did always used to work. Would a bad fuel pressure regulator cause this problem?

[fireguy50]

Check to see if the fuel pressure regulator is leaking fuel into the vacuum hose.

Does the fuel pressure drop with vacuum?

Are there any CM codes?

[MaddMartigan]

Check to see if the fuel pressure regulator is leaking fuel into the vacuum hose.

Does the fuel pressure drop with vacuum?

Are there any CM codes?

Actually, the fuel pressure drops with no vacuum. But that's normal since the fuel pressure is supposed to be 39psi with no vacuum and it's a bit higher with vacuum. I also checked the vacuum hose and there didn't appear to be any fuel in it.

I'm not sure about the CM codes since I haven't heard that term before.

[MaddMartigan]

I also want to add to this that I did some experimenting on this earlier today and I got the car to running slightly better by leaning out the MAF curve. In the end it's almost like the car adapted back to running more rich though.

I wonder if maybe both of my O2 sensors have died?

[MaddMartigan]

I have it figured out now. Turns out that I have a stuck fuel injector.

Thanks for the help.

[fireguy50]

GREAT! (that it's fixed)

Remember, not all problems can be fixed with a laptop, now that you have one hook up to the car.

Did you find one spark plug didn't match the others?

I'll bet you had a O2 sensor CM fault code for that side of the engine.
CM codes are after KOEO codes, you have to wait for the computer to give ALL the codes.

Or if you dataloged the problem, KAMRF would have be pegged 25% on 1 side, and the HEGO volts would be pegged on the same side.

Next time you ask for help, try to gather as much data.

[MaddMartigan]

Thanks for the tips.

Honestly, this problem was so weird and severe for me that I didn't know where to start. The car wouldn't idle long enough for me to do any kind of real testing.

I am certainly learning these things too so any guidance on the kind of data I need to collect is always helpful. I am getting a better grip on what I should be checking so every little bit you guys provide helps a lot.

Thanks again.

[rockin_rick]

CM codes are after KOEO codes, you have to wait for the computer to give ALL the codes.

CM = continous memory

These are the codes stored when an error occurs during normal engine operation. KOEO codes are what the computer finds while running the KOEO test. They have the same numbers and the same meanings as the KOEO codes. They are seperated by a single MIL light flash (sometimes referred to as a code 10).

Rick

[MaddMartigan]

CM codes are after KOEO codes, you have to wait for the computer to give ALL the codes.

CM = continous memory

These are the codes stored when an error occurs during normal engine operation. KOEO codes are what the computer finds while running the KOEO test. They have the same numbers and the same meanings as the KOEO codes. They are seperated by a single MIL light flash (sometimes referred to as a code 10).

Rick

Ok, I see. My code scanner manual refers to those as KOER as opposed to CM. I couldn't get the car to idle long enough to check those anyway.

I have actually done a cylinder balance check which is performed after you read the CM codes when you follow the proper procedure.

It's pretty valuable if you ever need to do that kind of troubleshooting.

[rockin_rick]

For clairity, there are 3 sets of codes:

During KOEO:
-KOEO
-CM

During KOER:
-KOER
-and the optional forth, cylinder balance

The CM are read with the engine off, so you should have gotten them.

Rick

[MaddMartigan]

Ah, I see now.

Do the CM codes cause a CEL that is one when the car is started?

[rockin_rick]

I'd set your FP to 39psi, vac disconnected from FPR.

How fast does your FP bleed off (time it takes from fuel pump off to 0 psi)? Do you have a rail mounted gauge? My autometer took a crap on me within a couple thousand miles. Too much vibration.

I think that your injectors are a bit larger than necessary. That sometimes leads to poor idle quality (because of the small PW at idle). Did you get a good deal, or have plans for a power adder?

Have you changed your injector offset vs battery voltage function for those injectors?

Rick

[rockin_rick]

Ah, I see now.

Do the CM codes cause a CEL that is one when the car is started?

I think so.

Check out (one of the links that I posted in the other thread) viewtopic.php?t=4540
If you've got codes, these will tell you EXACTLY what to look for and in what order. Besides endless other info.

Rick

[fireguy50]

Rick the fuel pressure bleed off because the injector was stuck open

I would double check the fuel pressure however:

[rockin_rick]

Rick the fuel pressure bleed off because the injector was stuck open

Duh

Rick

[fireguy50]

CHANGE THE OIL SOON!
all that extra fuel delutes the oil.

I forgot that detail

[MaddMartigan]

CHANGE THE OIL SOON!
all that extra fuel delutes the oil.

I forgot that detail

Yep, that was the plan before I tried to start it again.